Truss beams constructed by interconnecting a plurality of triangular frame elements to form an elongate structure having an equilateral cross-section have previously been disclosed by the instant inventor. An example of a prior art triangular truss beam and its constituent elements and interconnections is depicted in FIGS. 1a to 1c and is illustrated, described and claimed in U.S. Pat. No. 4,633,566 issued Jan. 6, 1987 to the instant inventor and assigned to the assignee of the instant application. An example of a square truss beam and its constituent elements and interconnections, as disclosed in copending application Ser. No. 808,602, filed Dec. 12, 1985 by the instant inventor, and assigned to the assignee of the instant application, is depicted in FIGS. 2a to 2c. Although the beams shown in FIGS. 1b and 2b can be constructed to any desired length within practical limits, they do not readily lend themselves to being interconnected to form larger multi-dimensional structures such as may be desired in a non-terrestrial environment. For example, while it is possible to simply butt the end of one beam against the side of another beam and to join them by conventional techniques, such an attachment will result in double strutting, i.e., a strut of one beam will be parallel and adjacent to a strut of the other beam. Furthermore, in a non-terrestrial environment beams so constructed may be difficult to join by the use of conventional techniques. A similar problem arises when it is desired to attach equipment or other devices to such a beam.